水基钻井岩屑对土壤的环境风险评价分析

Risk Analysis of Soil Pollution by Water-Based Drilling Cuttings

对水基钻井岩屑环境风险的研究通常主要集中在特征污染物的含量测定和标准对比,缺乏对不同井段、不同钻井液体系水基钻井岩屑细化分类后的环境风险分析。文章系统研究了不同条件下水基钻井岩屑对土壤的环境风险,明确了主要污染物质的迁移方式和转化途径。依照土壤质量标准对不同条件下的水基钻井岩屑进行重金属、有机物等主要污染物的测定分析,明确了深层、浅层钻井岩屑环境风险性的差异,同时对主要污染物溯源,分析污染物进入环境水系统的可能性。结果表明,无论是重金属含量、有机污染物含量还是浸出液特征污染物含量,在深层、浅层水基钻井岩屑中均具有较大差异,从地层矿物组成来看,环境风险仅集中在深层的钻井岩屑中,挥发性有机物虽广泛存在于水基岩屑,但含量很低,而浸出液的污染指标则需重点关注。研究发现,深层、浅层水基岩屑的环境风险差异明显,采用分质分类精细化处理水基岩屑具有原理上的可行性。

Usually,studies on the environmental risk of water-based drilling cuttings focus on the determination of characteristic pollutants and comparison of standards,but there is a lack of analysis on the environmental risk of water-based drilling cuttings in different layers and different drilling fluid systems after refinement and classification.The main pollutants such as heavy metals and organic matter were measured and analyzed according to soil quality standards,and the differences in environmental risk between deep and shallow drilling cuttings were clarified,while the sources of the main pollutants were traced and the possibility of pollutants entering the environmental water system was analyzed.The results show that both the heavy metal content,organic pollutant content and the pollutant situation of leachate have large differences in the deep and shallow water-based drilling cuttings.From the perspective of the mineral composition of the formation,the environmental risk is only concentrated in the deep drilling cuttings,and the volatile organic compounds,although widely present in the water-based cuttings with very low content,but the pollution index of leachate needs to be focused on.It was found that the environmental risk of deep and shallow water-based cuttings differed significantly,and it is feasible in principle to adopt the fine-grained treatment of water-based cuttings by quality classification.